A ship is made in a streamline shape in her bow and stern portions for thereby minimizing an external air resistance or a strong sea wind resistance, by which the ship can sail faster.
Since the ship is made in a streamline shape in her bow and stern portions, the ship can sail faster without any resistances such as sea wind in her bow and stern portions. However the ship does not have any means for minimizing a cross wind resistance in the course of sailing.
In case of a large size ship or a super large size ship such as an oil tanker or a gas carrier, a container carrier, a bulk carrier and an aircraft carrier which has more than 40˜80 m wide, 300˜460 m long and 10˜30 capacity tonnage, the area exposed from her side surface is very large, so the ship has a relatively larger cross wind resistance in the course of sailing, whereby a lot of a sailing energy loses, and a sailing might be slowed down.
Since a conventional ship is made in a streamline shape only in her bow and stern portions, the ship has a lot of wind resistance. As described above, in case of a large size ship or a super large size ship such as an oil tanker or a gas carrier, a container carrier, a bulk carrier and an aircraft carrier which has more than 40˜80 m wide, 300˜460 m long and 10˜30 capacity tonnage, the ship has a relatively larger cross wind resistance in the course of sailing, by means of which a lot of a sailing energy loses, and a sailing might be slowed down.